This invention relates to the production of electric energy using salts and minerals present in seas and oceans or lakes and the salinity gradient present in bodies of water or between bodies of water (e.g., between water at the mouth of a river and the sea or ocean into which the river flows).
In the discussion to follow reference to seas or oceans is meant to include any body of water (e.g., lake or pond) containing sails and/or minerals. Salinity as used herein refers to the saltiness or dissolved salt content (such as sodium chloride, magnesium and calcium sulfates, and bicarbonates) of a body of water (i.e., Salinity is a measure of the amount of salts in the water). Salts that dissolve in water break into positively and negatively charged ions. Conductivity is the ability of water to conduct an electrical current, and the dissolved ions are the conductors. The major positively charged ions are sodium (Na+), calcium (Ca+2), potassium (K+) and magnesium (Mg+2). The major negatively charged ions are chloride (Cl−), sulfate (SO4−2), carbonate (CO3−2), and bicarbonate (HCO3−). Nitrates (NO3−2) and phosphates (PO4−3) are minor contributors to conductivity, although they are very important biologically. Increasing the number of dissolved ions increase salinity as well as conductivity, the two measures are related. The salts in sea water are primarily sodium chloride (NaCl), although as noted above there are other materials present (e.g., magnesium sulfate and calcium). Sea water is about 220 times saltier than fresh lake water. Numerous chemical elements have been identified in sea water.
There is a constant growing need to generate electric power. There is also a constant search to find new ways of producing energy which does not rely on fossil fuel. There is likewise a great demand for sources of clean renewable energy.
Known schemes for producing electrical energy from saltwater or salinity gradients are very complicated and cumbersome and not economically viable.
It is recognized that the salinity difference between seawater (relatively high salinity) and river water (relatively low salinity) represents a renewable source of enormous entropic energy, but extracting useful energy efficiently remains a difficult challenge.
Applicant has conducted experiments showing that electric energy may be produced by using the various properties of different chemicals present in bodies of water.
It is an object of the invention to provide a simple and direct means of generating electric energy from salts and minerals present in bodies of water and storing the generated energy or making it available for distribution directly or indirectly.